Introduction

Intent

This procedure describes the use of an optical time-domain reflectometer (OTDR) to indirectly measure the loss and reflectance of a splice or connector.

Other methods

Loss or reflectance measurements may be obtained also by using FOTP-34 or FOTP-107. The latter values will be accepted as correct in the event of a dispute.

Trace defects

Some OTDR/fiber combinations appear to give "noisy" traces that may be repeatable for a given OTDR but not against other OTDRs with the same fiber. These appear to be related to polarization and coherence effects, and are being studied in FO-6.6. Some OTDR manufacturers offer noise filters, internal or external to the OTDR, and care shall be taken that these do not mask "true" artifacts of the trace. Moreover, parts of the trace that are noisy due to low signal-to-noise ratio shall not be used.